本项目拟对多年冻土区冻融过程协同植被覆被变化对土壤蒸散发、土壤入渗及土壤水热变化过程的影响开展研究。通过对土壤蒸散发、土壤入渗和水热变化过程的野外原位观测试验，在不同冻土活动层冻融过程变化和植被退化条件下，分析在多年冻土区冻融过程和植被覆被变化对土壤蒸散发和土壤入渗关键过程的影响特征。对冻土活动层温度、土壤水分、土壤属性及植被等要素的变化监测和分析，解释植被退化与土壤属性改变对土壤水热过程的影响特征，揭示冻土区土壤蒸散发和土壤入渗过程与冻融过程和植被退化之间的耦合关系和相互作用机理；通过实际观测资料的分析，进一步完善适合冻土区的蒸散模型和入渗解析模型，对气候变化条件下冻土区蒸散过程和入渗过程变化进行分析和预测。

The aim of this project is to study the influence offreeze-thaw processes and vegetation changes on soil evapotranspiration, soil infiltration and hydrothermal change process in permafrost regions.Under the diffferent conditions of active layer freeze-thaw processes and vegetation degeneration, the influence of freeze-thaw processes and vegetation changes on the key processes of soil evapotranspiration and soil infiltration is analysed in permafrost regions by the in-situ observation experiment on soil evaporation, soil infiltration and hydrothermal processes. Through the monitoring andanalysis of active layer soil temperature, soil moisture, soil properties and vegetation, the characteristics of the influence of vegetation degeneration and soil properties changes on soil hydrothermal process is explained, and the coupling relationship mechanism between soil evapotranspiration and soil infiltration and freeze-thaw processes and vegetation degeneration is revealed in permafrost regions. Through the analysis of actual observation data,the evapotranspiration model and infiltration analytical model suitable for permafrost regions are further improved, which can analyze and predict the changes of evapotranspiration and infiltration processes in permafrost regions under climate change.